Suction box cover



July 28, 1959 PREVQST 2,896,711

SUCTION BOX COVER Filed July 11, 1955 96 i I. I02

33 33 F76. 5. H6 5. 93 Q4 70 7/ (MENTOR.

73 BRUNO E. PRE'M'OSZ 67/ 62 ATTORNEYS.

W. Bolton & Sons, Inc., Lawrence, Mass, a corporation of Massachusetts Application July 11,1955, Serial No."521,020 6 Claims. (Cl. 162-374) This invention relates to suction boxes used in Fourdrinier machines and especially to end-of-grain wood block .covers for the same.

Such suction boxes extend longitudinally under a traveling Fourdrinier wire transversely to the wvire and draw liquid out of the paper stock carried by the wire. The wire thus travels over the lateral dimension of the box and tends to wear down the perforated suction box cover.

It has heretofore been proposed to provide removable covers for suction boxes made of a plurality of end of grain wood blocks extending obliquely of the direction of travel of the wire and slideably supported on guides or tracks extending longitudinally of the suction box. Such oblique blocks have been elongated and narrow and have extended the full lateral dimension of the suction box cover whereby they have been twelve or more inches in length. However, it has been difficult and costly "to secure end-of-grain maple wood of sufiicient size and v United States Patent quality to form such blocks and, since the blocks must be perforated with suction holes, they have been extremely weak and fragile.

It is an object of this invention to provide a. suction box with an end-of-grain wood cover which isless costly and of greaterstrength than former constructions.

Another object of the invention is to provide a we tion box cover formed into at least two laterally spaced, longitudinally extending sections, each section being preferably less than eight inchesin width to accommodate shorter and sturdier blocks of end-of-grain wood.

A further object of the invention is to provide a suction box and cover wherein the cover is in several longitudinally extending sections with ,each section capable of accommodating end-of-grain blocks similar in perfora tions or different in perforations from those of the other sections.

Still another object of the invention is to provide a novel end-of-grain suction block of the oblique type in which alternate deep grooves in each block overlap each other and are arranged to form elongated longitudinally extending perforations'in a suction box cover equal in' *Fig. 1 is a fragmentary plan view of a single suction box cover divided into a plurality of laterally narrow, full length sections in accordance with the invention.

Fig. 2 is an end view in section on line 22 of Fig. 1. Fig. 3 is an enlarged cross sectional view of a side rail member or an endlocking member of the invention.

Fig. 4 is an enlarged cross sectional view of an intermediate rail member of'the invention.

i wood blocks.

Well known in the art and forming no part of this invention.

The suction box cover 26 of this invention includes a pair of metal side rail members 27 and 28, each co-extensive with a side wall 21 or 22 and each having holes such as 29 or 30 whereby they may be removably affixed to the side walls. As indicated, a horizontal flange such as 31 or 32 may be provided on the side walls 21 and 22, there being threaded holes 33 therein to receive .machine screws 34 for retaining the side rail members thereon. Preferably each side rail member 27 or 28 is of inverted U shape cross section. Each is provided with an inwardly facing, longitudinally extending continuous tongue 36 or 37. At least one intermediate rail member 38 is provided, co-extensive with members 27 and 28 and with side walls 21 and 22. If only one member 38 is provided it is centrally disposed laterally between the outer side members 27 and 28. As shown, if additional members 38 are provided they are equally spaced apart between the side members. Each member 38 is provided with a hole such as 39 at each opposite end for receiving a screw 40 for afiixing the same to an intermediate point on an end wall such as 23. Preferably, member 38 is of inverted U shape in cross section. Member 38 is provided with outwardly facing, longitudinally extending continuous tongues 41 and 42 on each opposite side thereof.

Suction box cover 26 also includes a plurality of metal end lock members such as 44 and 45, of inverted U shaped cross section, each having holes such as 46 and 47 for screws such as 48 and 49 whereby they may be aflixed to an end wall such as 23. Each end element is preferably provided with a continuous inwardly facing tongue such as 50 corresponding to tongues 36, 37, 41 and 42 and is also provided with \block clamping means in theform of a thrust screw 51.

It should be noted that the side rail members 27, 28 and 38 together with the end rail members such as 44 and 45 at each opposite end of the cover 26 thus form at least two laterally spaced longitudinallyextending openings such as 58, 59 and 60 above the suction box 20, each opening having tongues to slideably receive end-of-grain Each opening 58 and 59, eight inches or less in width, or less than half the width of the suction box, and extends the full length of the suction box. It is,

therefore, possible to span each said opening with eight inch end-of-grain blocks cut perpendicularly or obliquely from lumber such as maple of about eight inches in width. It is preferable, however, to use more intermediate members such as 38 and thus reduce the width of the openings and the length of the blocks even further to make use of lumber of less diameter and achieve an even sturdier construction.

The suction box cover 26 is especially useful in supporting end-of-grain wood blocks such as 62 and 63 Which are of the oblique type with a parallelopiped body and an upper and lower surface in the form of a parallelogram. Such blocks have heretofore been provided 3 gated oblong and curvilinear hole between each pair of abutting blocks as at 66 or with a plurality of shallow spaced apart grooves on each side to forma plurality of spaced obliquely aligned round or oval holes as at '67 between each pair of abutting blocks. By obliquing the lines of perforations or the single elongated perforations mentioned above all of the area of the traveling Fourdrinier wire is successively exposed to suction bythe'pen forations.

However, in many instances it has been desirable to provide suction holes which extend contmuously full length of the suction box and completely across the Fourdrinier wire whereby instead of successive suction by staggered or obliqued perforations, a straight line area right across the wire is simultaneously exposed to suetion. Usually such suction box covers have been in the form of suction bars extending the full length of the box and laterally spaced apart to form full length suction slots therebetween and special supporting frames of metal have been required therefor. In this invention, a satisfactory substitute for such full length slotted covers is disclosed in the short blocks such as shown at 62 and 63. As indicated in Fig.1 while the slots formed by blocks .62 and 63 are not continuous for the full length of the suction box, each pair of lines of slots traversed by the wire does expose the entire width of the wire to suction. Thus if six lines of slots are used, the wire is successively exposed to suction over its entire width three times in passing over the suction box cover 26. The term groove is used herein when describing an individual block such as 62 or 63 since each block is milled to form its grooves such as 75, 76, 77 and 78. When two blocks such as. 62 and 63 are placed together in a suction box cover the grooves such as 75, 76, 77 and 78 jointly form apertures such as 79, 80 and 81 termed suction slots or suction holes herein.

As shown in Fig. 6, each block such as 62 is formed of end-of-grain wood such as maple preferably not exceeding eight inches in length and one or two inches in width. The end-of-grain upper face 68 and lower face 69 are each in the form of a parallelogram while end faces 70 and 71 contain the tongue grooves 64 and 65 for slideably supporting the block on tongues 36 and 41 and are parallel to rail members such as 27, 28 and 38. The side faces such as 72 and 73 of each block are obliqued as shown and may also have a tongue and groove connection with abutting blocks if desired.

Instead of the usual shallow, grooves forming holes such as at 67, deep grooves such as 75 and 76 are alternately formed along the length of each block such as 62 from each opposite side face 72 and 73. The corresponding deep groves such as 77 and 78 in every other block such as 63 are reversed in position to jointly form the elongated suction slots or holes such as 79 extending longitudinally of the suction box and transversely of a wire passing thereover. Each deep groove such as 75, extends well beyond the longitudinal centre line of the block and terminates at a closed end proximate the opposite side face of the block. Thus the alternate holes such as 79, 8t) and 81 overlap each other to a considerable degree, the suction surface of the blocks are greatly increased and the remaining non perforated web of each block is of greatly reduced area.

However, it should be noted that there is no continuous straight line Web of material in any block and in addition the end-of-grain nature of the block adds to its weakness. The provision of the intermediate rails such as 38 in the suction box cover 26 permit a shorter block to be used and permit the circuitous outline of blocks such as 62 and 63 without breakage thereof.

It will be obvious that a great variety of suction patterns are possible with this invention in that in the same suction box cover, blocks. having short longitudinal holes as at 67 may be inserted in one opening 59 and oblique blocks having long, longitudinal holes 79, 80 and 81 may be used in another opening 58 and blocks having long lateral holes, as at used in another opening 60. It is only necessary to remove an end rail member such as 44 to replace or substitute blocks, together with any required fillers such as block 83, since all of the blocks are grooved as at 64 and 65 to. slide on the tongues of the members 27, 28 and 38.

As best shown in Figsl, 2 and 5.,the suction box cover of this invention is provided with laterally extending supporting braces 91 for the intermediate rail members 38 preferably in the centre and proximate each end of the members 38. The braces 91 are relatively thin in order not to block suction in the holes they traverse but are sufiiciently wide to accommodate threaded holes such as 92 for receiving the threads of machine screws 93 seated in holes such as 94 spaced along the rail members 38. Each opposite end 95 or 96 of each brace 91 is cut away to form a shelf portion 97 and 98 adapted to rest on a side wall flange 31 or 32 of suction box 20. Similarly each rail member 27, 28 and 38 is slotted as at 99 and 100 to receive the ing the side and intermediate rails into a pre-formed frame or grid and with the suction blocks in place or shipped separately as desired. When the blocks are shipped in place on the frame, the end members 44 may be held in position by suitable detachable strapping passing under the braces 91 and back over the upper surface of the blocks. Sometimes it is desirable to also weld each end and 96 of the braces. 91 to the side walls of the suction box for added rigidity.

I claim:

1. A cover for a paper machine suction box, said cover comprising a pair of metal side rail members each co-extensive with, and adapted to be aflixed on one of the opposite, longitudinally extending side walls of a suction box and each having an inwardly facing, longitudinally extending, continuous tongue therealong; at least one intermediate metal rail member, co-extensive with said metal side rail members and positioned in the space therebetween, each of said intermediate metal rail members being adapted to be aflixed at each opposite end thereof to one of the laterally extending end walls of a suction box and having an outwardly facing, longitudinally extending, continuous tongue on each opposite side thereof; a plurality of metal end lock members, each adapted to be aifixed to one of the opposite, laterally extending end walls of a suction box between adjacent ends of an adjacent pair of said rail members and each end lock member having block clamping means thereon, and a plurality of separate elongated wood blocks, having suction perforations therethrough from an end-of-grain upper face to an end-of-grain lower face and adapted to fill the space between each pair of adjacent rail members, each said elongated block abutting along its opposite side faces with adjoining blocks and having a tongue groove in each opposite end face slidably supported on the adjacent longitudinally extending tongue of a side or intermediate rail member.

2. A combination as specified in claim 1 wherein each said block extends laterally of the suction box less tend well beyond the longitudinal centre line of the block and nearly to the opposite side face to thereby overlap each other.

4. A combination as specified in claim 1 wherein each said elongated block extends obliquely relative to the said cover and is alternately deep grooved from each opposite oblique side face with grooves which extend therethrough beyond the longitudinal centre line of the block and nearly to the opposite oblique side face.

5. A combination as specified in claim 1 plus at least one brace extending laterally of said cover and attached at each opposite end to one of said side rail members, said brace being adapted to support said intermediate rail member and said rail members each being slotted to receive the upper portion of said brace.

6. A suction box for use with Fourdrinier machines, said box having longitudinally extending side walls and laterally extending end walls, a rigid, bodily transportable frame comprising a pair of outer longitudinal rail members each fixed to and extending along one of said side walls from end to end thereof; at least one intermediate longitudinal rail member fixed at each opposite end to an intermediate point on one of said end walls and extending longitudinally in the space between said outer rail members; end lock members each closing the space between a pair of adjacent ends of an adjacent pair of said rail members and removably attached to said end walls; at least one intermediate lateral brace attached at each opposite end to a side rail member, supported on a side Wall of said box and extending laterally thereacross, under and in support of, said intermediate rail member; inward facing tongues on each of said side rail members and outward facing tongues on each of said intermediate rail members, said framework forming at least two laterally spaced, longitudinally extending openings and at least two suction box cover sections, adapted to fill said openings, each said section being formed of a plurality of separate, perforated, end-of-grain wood blocks longitudinally grooved for slidable movement on, and support by an inward facing tongue of a side rail member and an outward facing tongue of an intermediate rail member.

References Cited in the file of this patent UNITED STATES PATENTS 751,095 McAnulty et a1 Feb. 2, 1904 1,236,359 Reynolds Aug. 7, 1917 1,608,202 Compton Nov. 23, 1926 1,657,509 Latham Jan. 31, 1928 2,042,198 Swauger May 26, 1936 2,346,785 Proulx Apr. 18, 1944 2,408,176 Proulx Sept. 24, 1946 2,682,813 Scofield July 6, 1954 2,712,776 Wagnknecht July 12, 1955 FOREIGN PATENTS 637,639 Great Britain May 24, 1950 

